Beverage can end with reduced countersink

ABSTRACT

The present invention describes an improved beverage can end which utilizes less material and has an improved internal buckle strength based on the geometric configuration of the chuck wall, inner panel wall, central panel and reduced depth between the countersink and crown of a circular end wall.

[0001] This application claims priority of U.S. provisional patentapplication Serial No. 60/262,829 having a filing date of Jan. 19, 2001,and is incorporated herein in its entirety by reference.

FIELD OF THE INVENTION

[0002] The present invention generally relates to beverage can ends, andmore specifically metallic beverage can ends used for interconnection toa beverage can body.

BACKGROUND OF THE INVENTION

[0003] Beverage cans and more specifically metallic beverage cans aretypically manufactured by interconnecting a beverage can end on abeverage container body. In some applications, two ends may beinterconnected on a top side and a bottom side of a can body. Morefrequently, however, a beverage can end is interconnected on a top endof a beverage can body which is drawn and pressed from a flat sheet ofblank material such as aluminum. Due to the potentially high internalpressures generated by carbonated beverages, both the beverage can bodyand the beverage can end are typically subjected to internal pressureswhich at times can exceed 100 psi.

[0004] Thus, the beverage can ends must be durable to withstand highinternal pressures, yet manufactured with extremely thin materials suchas aluminum to decrease the overall cost of the manufacturing processand weight of the finished product. Accordingly, there exists asignificant need for a durable beverage can end which can withstand thehigh internal pressures created by carbonated beverages, and theexternal forces applied during shipping, yet which are made fromdurable, lightweight and extremely thin metallic materials. It is afurther problem to provide a beverage can end which is stackable, andthus can be shipped in bulk. There is a need for a beverage can endwhich further provides additional head space when double-seamed to abeverage can body, and thus allows for a reduction of materials andassociated costs with respect to the beverage can body. Finally, thereis a need for a beverage can end which does not accumulate dirt, dustand beverage product in the “mote” created by the countersink.

[0005] The following application describes an improved beverage can endwhich is adapted for interconnection to a beverage can body and which inone embodiment has a countersink with a reduced depth, as measured fromthe crown of the circular end wall, and a central panel area whichsignificantly saves material costs yet can withstand significantinternal pressures. In other embodiments, an improved beverage can endis provided which has a central panel positioned above the crown of thecircular end wall, and an opening tab which is positioned below theheight of the central panel.

SUMMARY OF THE INVENTION

[0006] Thus, in one aspect of the present invention, a beverage can endis provided which can withstand significant internal pressures exceeding100 psi and yet saves between 5% and 12% of the material costsassociated with typical beverage can end manufacturing. This isaccomplished primarily by reducing the overall depth of the countersinkfrom the height of the crown, the crown being defined herein as theuppermost edge of the circular end wall or the top edge of the doubleseam after the beverage can end is interconnected to the beverage canbody. Preferably the distance from the crown to the lowermost portion ofthe countersink ranges between about 0.110 inches and 0.270 inches,while the distance from the lowermost portion of the countersink to themaximum height of the central panel is typically between about 0.030 and0.130 inches.

[0007] In another aspect of the present invention, a beverage can end isprovided which is manufactured with conventional manufacturing equipmentand thus eliminates the need for expensive new punches and pressesrequired to make the beverage can end. Thus, existing and well knownmanufacturing equipment and processes can be implemented to quickly andeffectively initiate the production of an improved beverage can end inan existing manufacturing facility.

[0008] Another aspect of the present invention to provide a beverage canend is provided which is stackable for shipping purposes, and which hasan opening tab which is not an obstruction for stacking purposes and yetreadily accessible for a user's fingers. Thus, in another embodiment ofthe present invention the opening tab is positioned in a recessedportion below the central panel. In one preferred embodiment of thepresent invention, a beverage can end is provided which has a centralpanel elevated above the crown of the double-seamed beverage can end,and an opening tab positioned below an uppermost portion of the centralpanel. This configuration has been found to reduce material costs sincethe headspace in the can is increased, thus reducing the material andassociated costs in the beverage can body. Further, by raising thecentral panel above the height of the crown, increased strength has beenrealized as a result of the improved “pressure vessel” geometry of thecan end.

[0009] It is another aspect of the present invention to provide abeverage can end which saves material costs by utilizing improvedgeometry and reducing the size of the blank, as opposed to utilizingthinner materials which are susceptible to failure. Thus, the integrityand strength of the beverage can end is not compromised, while materialcosts are significantly reduced as a result of the blank reduction.

[0010] Thus, in one aspect of the present invention, a metallic beveragecan end is provided which comprises:

[0011] a circular end wall adapted for interconnection to a beverage canbody, said circular end wall having a crown on an upper most edge;

[0012] a chuck wall integrally interconnected to said circular end walland extending downwardly therefrom at a chuck wall angel θ of betweenabout 0 and 15 degrees;

[0013] a countersink integrally interconnected to said chuck wall andextending downwardly therefrom;

[0014] a central panel integrally interconnected to said countersink andextending upwardly therefrom to an elevation at least about theelevation of said crown; and

[0015] an opening means positioned on said central panel which ispositioned at an elevation no greater than said uppermost edge of saidcentral panel, wherein the beverage can may be selectively opened.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016]FIG. 1 is a front elevation view depicting an overlay of fourdifferent embodiments of a new beverage can end with a reducedcountersink and the central panel shown below the crown;

[0017]FIG. 2 is a front elevation view of one embodiment shown in FIG. 1and identifying dimensions related thereto;

[0018]FIG. 3 is a front elevation view of one embodiment shown in FIG. 1and identifying dimensions related thereto;

[0019]FIG. 4 is a front elevation view of one embodiment shown in FIG. 1and identifying dimensions related thereto;

[0020]FIG. 5 is a front elevation view of a prior art beverage can end;

[0021]FIG. 6 is a front elevation view of one embodiment of the presentinvention with the central panel positioned above the crown of thecircular end wall;

[0022]FIG. 6A is a front elevation view of another embodiment of thepresent invention with the central panel having an elevationapproximately the same as the crown of the circular end wall;

[0023]FIG. 6B is a front elevation view of another embodiment of thepresent invention with a reduced countersink depth as measured from thecrown of the circular end wall;

[0024]FIG. 7 is a front elevation view of one embodiment of the presentinvention wherein the central panel is raised above the crown and a pulltab is positioned below an uppermost edge of the central panel; and

[0025]FIG. 8 is a front elevation view of two alternative embodiments ofthe present invention showing the central panel raised above the crown,and pull tab positioned below an uppermost edge of the central panel,with a prior art beverage can end provided for reference purposes;

[0026]FIG. 9 is a front elevation view of one embodiment of the presentinvention and identifying the parameters used to equate the finaldimensions of the central panel;

[0027]FIG. 10 is a front elevation view of one embodiment of the presentinvention with the central panel elevated above the crown of thecircular end wall; and

[0028]FIG. 11 is a front elevation view of the embodiment shown in FIG.10, but with the pull tab located at an elevation below the upper edgeof the central panel.

DETAILED DESCRIPTION

[0029] Referring now to the drawings, FIGS. 1-8 generally depict frontelevation views of various embodiments of the present invention. Morespecifically, FIG. 1 is an overlay showing the various geometricconfigurations of numerous embodiments of the present beverage can end 2and countersink 8, while FIGS. 2-5 are various embodiments of the canend shown in FIG. 1 with dimensions provided therein for greater detail.FIGS. 6-8 are front elevation views which show alternative embodimentsof the present invention with the central panel 10 raised above or equalto the crown 14, as well as an embodiment with the pull tab 18positioned below the elevation of the uppermost portion of the centralpanel 10.

[0030] In general, a beverage can end 2 of the present invention iscomprised of a circular end wall 4 or curl which is interconnected to achuck wall 6 and which extends downwardly at a chuck wall angle θ to acountersink 8. The countersink generally represents the lowermostportion of the beverage can end and is integrally interconnected to aninner panel wall 12 which extends upwardly toward the central panel 10in either a substantially vertical direction or at an inner panel wallangle φ. Alternatively the inner panel wall 12 may have an arcuate shapewith a distinct radius of curvature. The “curl” or circular end wall 4has an upper edge generally defined as a crown 14, and which typicallyrepresents the highest portion of the beverage can end 2. As recognizedin the art, the crown may also be referred to as the “chime” once thebeverage can end 2 is double seamed to the beverage can body 16.

[0031] The present invention in one embodiment is distinct from priorart beverage can ends in that the height of the countersink 12 issignificantly reduced from typical beverage can ends 2. By eliminatingthe depth of the countersink 8 with regard to the crown 14, significantmaterial savings between about 2.5% and 11% have been realized. Therelationship between the height of the countersink 8, the angle of thechuck wall θ, and the diameter of the center panel 10 can generally bedescribed with the following formula which is additionally shown in FIG.9:

D2 =2×(A−B)×tan (θ) plus D1 where

[0032] a) D1 equals the starting panel radius center diameter;

[0033] b) D2 equals the final panel radius center diameter;

[0034] c) θ equals the chuck wall angle;

[0035] d) A equals the starting countersink length; and

[0036] e) B equals the final countersink length.

[0037] Referring now to FIG. 1, four different embodiments of thepresent invention are provided herein which depict ranges of thecountersink depth, the chuck wall angle θ, the height of the centerpanel 10, and the overall diameter of the central panel 10. As shown, asthe height from the crown 14 to the countersink 8 is reduced, thediameter of the central panel 10 increases.

[0038] In each of the specific embodiments shown in FIGS. 2-5, theheight between the lowermost portion of the countersink 8 and the heightof the central panel 10 is generally about 0.090 inches, although theremaybe variations depending on other geometric features of the beveragecan end 2. Further, as shown in FIG. 1 the panel height above thelowermost portion of the countersink 8 may generally have a range ofbetween about 0.030 and 0.130 inches. As seen in FIG. 1, the inner panelwall 12 is oriented at an angle φ in a substantially vertical directionwhen extending upwardly from the countersink 8, but may have an angle ofbetween about 0-10 degrees or be arcuate in shape as previouslydiscussed. Further, the countersink radius in a preferred embodiment isestimated to be between 0.010 to 0.020 inches, while the radius of theinterconnection between the central panel 10 and the inner panel wall 12is preferably between about 0.010 inches to 0.030 inches. As furtheridentified in FIG. 1, the distance from the crown 14 in one embodimentis 0.130 inches to the lowermost portion of the countersink 8, and inother embodiments is 0.150 inches, 0.180 inches and 0.270 inches asshown. Preferably with all of the embodiments described herein, the gageof the metallic material (typically aluminum) is between about 0.0050and 0.0140.

[0039] More specifically, FIG. 2 represents a beverage can end 2 with acountersink of about 0.130 inches as measured from the crown 14 to thelowermost portion of the countersink 8. In this particular embodiment,with a 12° 45′ chuck wall angle θ, the central panel has a diameter of1.879 inches as measured to the point of curvature of the central panel10 or a diameter of about 1.936 inches to the vertical inner panel wall12. The height of the central panel 10 in all embodiments shown in FIGS.2-5 have a distance from the lowermost portion of the countersink 8 ofabout 0.090 inches. In this particular embodiment, it has been foundthat a material reduction of about 10.95% can be realized over moreconventional beverage can ends with more pronounced countersink 8depths.

[0040] Referring now to FIG. 3, an alternative embodiment of the presentinvention is provided herein with a counter sink depth of 0.150 inchesas measured from the height of the crown 14. In this embodiment, theoutermost diameter of the central panel 10 is about 1.927 inches, with achuck wall angle θ of 12° 45′. Further, the radius at the intersectionbetween the inner panel wall 12 and the central panel 10 is 0.020inches, which is consistent with the other embodiments shown in theFIGS. 2-5. In this particular embodiment, a material reduction of about9.46% is realized as compared to conventional beverage can ends.

[0041] Referring now to FIG. 4, an alternative embodiment of the presentinvention is described herein with a height from the crown 14 to thelowermost portion of the countersink 8 of about 0.180 inches. In thisembodiment, with the central panel 10 elevated above the lowermostportion of the countersink a distance of about 0.090 inches, and with achuck wall angle θ of 12° 45′, the central panel has an outermostdiameter of 1.913 inches as measured to the respective inner panel walls12. Furthermore, in this particular embodiment the material reduction isestimated at about 7.05% over conventional beverage can ends.

[0042] Referring now to FIG. 5, a prior art beverage can is providedherein for reference purposes with respect to FIGS. 1-4. This drawingfurther identifies the significant reduction in the depth of thecountersink 8.

[0043] Referring now to FIGS. 6-6B, three alternative embodiments of thepresent invention are shown herein. More specifically, FIG. 6 shows oneembodiment of the present invention, wherein the central panel 10 iselevated above the crown 14 of the circular end wall 4. FIG. 6Arepresents an alternative embodiment, wherein the crown 10 is positionedsubstantially at the same height as the crown 14 of the circular endwall 4, while FIG. 6B is an embodiment more consistent with theembodiments shown in FIGS. 1-5, wherein the central panel 10 ispositioned below the crown 14 of the circular end wall 4, but thecountersink 8 depth from the crown 14 is still significantly reducedfrom prior art metallic beverage can ends.

[0044] Referring now to FIG. 7, another embodiment of the presentinvention is provided wherein the central panel 10 is shown elevatedabove the crown 14 of the circular end wall 4, and which furtherincludes a pull tab 18 positioned below and uppermost edge of thecentral panel 10 to selectively open the beverage can end. In thisparticular embodiment, the elevation of the central panel 10 above thecrown 14 has at least two distinct advantages over prior art designswhere the central panel 10 is positioned below the crown 14. First, bycreating a convex shaped central panel 10, significant improvements inburst and buckle resistance have been obtained, with improvementsestimated at between 2-10%. Thus, greater strength characteristics canbe realized by using a substantially convex geometric configuration.Furthermore, to provide for stackability of the beverage can ends 2prior to filling and double seaming with the beverage can body, the pulltab 18 is positioned below an uppermost portion of the central panel 10in a deboss or indentation 20 of about 0.070 inches. As appreciated byone skilled in the art, numerous types of pull tabs 18 or other openingdevices may be used as preferred by the filler or customer.

[0045] The second distinct advantage provided with the design shown inFIG. 7 is the increased head-space created by the elevated central panel10. The head-space is generally defined herein as the distance above thebeverage in the beverage can body and the central panel 10, which allowsfor expansion within the can due to freezing and/or excessive pressure.By increasing the amount of available head-space, the beverage can body16 may be reduced in height, thus substantially saving materials andassociated costs in the beverage can body 16.

[0046] Referring now to FIG. 8, two embodiments of the present inventionare shown overlayed herein, as well as a more typical prior art beveragecan for comparison purposes. More specifically, the beverage canidentified as “A” is shown with a substantially arcuate shaped centralpanel 10, which extends upwardly from the inner panel wall 12 andcountersink 8. The central panel 10 is curved inwardly but is raisedabove the crown 14 of the circular end wall 4. As further identified inthis drawing, the pull tab 18 is positioned below an uppermost edge ofthe central panel 10. A second embodiment of the present invention asshown in FIG. 8 is identified by “B” which shows the central panel 10having an arcuate shape and a pronounced radius of curvature but whichis oriented inwardly at a more accelerated rate than the embodimentshown in “A”. Furthermore, with the embodiment shown in “B”, theindentation 20 of the central panel 10 is positioned further inwardly,and thus having slightly less clearance between the pull tab 18 and thecentral panel indentation 20.

[0047] Referring now to FIG. 9, a front elevation view of one embodimentof the present invention is provided herein and which additionallydepicts the various parameters used to calculate the final panel radiusdiameter shown as D2 and also defined previously in the equation on page7. More specifically, the parameters include the starting panel radiuscenter diameter D1, the chuck wall angle φ, the starting countersinklength A, and the final countersink length B. With these parameters andassociated formula, it is thus possible to vary numerous parameters todefine a beverage can end 2 with a given central panel diameter, angleof chuck wall θ, etc.

[0048] Referring now to FIGS. 10 and 11, a front perspective view of twoembodiments of the present invention are provided herein, wherein thecentral panel 10 is raised above the crown 14 of the circular end wall4. Further, FIG. 11 shows the invention depicted in FIG. 10, but alsoincluding a pull tab 18 which is positioned below the upper edge of thecentral panel 10 and positioned within a central panel indentation 20commonly known in the art as the deboss. By positioning the pull tab 18in the central panel indentation 20, the stackability of the beveragecan ends may be maintained for shipment in bulk.

[0049] For clarity purposes, the following lists of components and theassociated numbering in the drawings are provided herein: No. Components 2 Beverage can end  4 Circular end wall  6 Chuck wall  8 Countersink 10Central panel 12 Inner panel wall 14 Crown 16 Beverage can body 18 Pulltab 20 Central panel indentation θ Chuck wall angle φ Inner panel wallangle

[0050] The foregoing description of the present invention has beenpresented for purposes of illustration and description. Furthermore, thedescription is not intended to limit the invention to the form disclosedherein. Consequently, variations and modifications commenced here withthe above teachings and the skill or knowledge of the relevant art arewithin the scope in the present invention. The embodiments describedherein above are further extended to explain best modes known forpracticing the invention and to enable others skilled in the art toutilize the invention in such, or other, embodiments or variousmodifications required by the particular applications or uses of presentinvention. It is intended that the dependent claims be construed toinclude all possible embodiments to the extent permitted by the priorart.

What is claimed is:
 1. A metallic beverage can end having a reducedcountersink, comprising: a substantially circular end wall adapted forinterconnection to a can body and having a crown defined by an uppermostedge; a chuck wall integrally interconnected to said substantiallycircular end wall on an upper end and extending downwardly therefrom ata chuck wall angle θ; a substantially concave countersink interconnectedto a lower end of said chuck wall, wherein a lowermost portion of saidcountersink is no greater than 0.270 inches from said crown; an innerpanel wall interconnected to said countersink and extending upwardlytherefrom; a central panel supported by said inner panel wall; and anopening means in operable engagement with said central panel, whereinthe metallic beverage can end can be selectively opened.
 2. The metallicbeverage can of claim 1, wherein said central panel is raised above saidcrown of said substantially circular end wall.
 3. The metallic beveragecan of claim 2, wherein said opening means is positioned below anuppermost edge of said central panel.
 4. The metallic beverage can ofclaim 1, wherein said central panel is elevated between about 0.030 and0.130 inches above said lowermost portion of said countersink.
 5. Themetallic beverage can end of claim 1, wherein said chuck wall angle θ isbetween about 0 degrees and 20 degrees as measured from an imaginaryvertical plane.
 6. The metallic beverage can end of claim 1, whereinsaid beverage can end is comprised of a metal material having a gagethickness of between about 0.0050 and 0.0140.
 7. The metallic beveragecan end of claim 1, wherein a diameter of said central panel is reducedin size as a lowermost portion of said countersink increases in distancefrom said crown.
 8. The metallic beverage can end of claim 1, whereinsaid central panel has a diameter no greater than about 1.936 incheswhen said lowermost portion of said countersink is no greater than 0.130inches from said crown.
 9. The metallic beverage can end of claim 1,wherein said countersink has a radius of curvature no greater than about0.020 inches.
 10. The metallic beverage can end of claim 1, wherein atleast a portion of said central panel has an arcuate, non-linearcross-sectional shape.
 11. The metallic beverage can end of claim 1,wherein said point of interconnection between said central panel andsaid inner panel wall has a radius of curvature no greater than about0.020 inches.
 12. A metallic beverage can end adapted forinterconnection to a beverage can body, comprising: a circular end wallhaving a crown defined by an uppermost edge of said circular end wall; achuck wall integrally interconnected to said end wall and extendingdownwardly at a chuck wall angle θ of between about 0-20 degrees; asubstantially concave countersink integrally interconnected to a lowerend of said chuck wall, said countersink having a lowermost portionwhich is no greater than about 0.270 inches in a vertical direction fromsaid crown; an inner panel wall integrally interconnected to saidcountersink and extending upwardly therefrom; a central panel integrallyinterconnected to said inner panel wall and having a height at leastabout the same elevation as said crown of said circular end wall; and anopening tab operably engaged to said central panel, wherein saidbeverage can end can be selectively opened.
 13. The metallic beveragecan end of claim 12, wherein said opening tab is positioned below anuppermost edge of said central panel.
 14. The metallic beverage can endof claim 12, wherein at least a portion of said central panel has anarcuate, non-linear cross-sectional shape.
 15. The metallic beverage canend of claim 12, wherein said beverage can is comprised of a materialhaving a thickness no greater than 0.0090 inch gage.
 16. The metallicbeverage can end of claim 12, wherein said countersink has a radius ofcurvature no greater than about 0.030 inches.
 17. The metallic beveragecan end of claim 12, wherein said inner panel wall extends upwardly atan angle φ of between about 0 and 10 degrees.
 18. The metallic beveragecan end of claim 12, wherein at least a portion of said central panel israised above said crown and a portion is positioned at an elevation nogreater than the elevation of said crown.
 19. The metallic beverage canend of claim 12, wherein when said beverage can end is double-seamed toa beverage can body a head-space is created of at least about ______inches.
 20. A beverage can end adapted for interconnection to a beveragecan body, comprising: a circular end wall adapted for interconnection toa beverage can body, said circular end wall having a crown on an uppermost edge; a chuck wall integrally interconnected to said circular endwall and extending downwardly therefrom at a chuck wall angel θ ofbetween about 0 and 20 degrees; a countersink integrally interconnectedto said chuck wall and extending downwardly therefrom; a central panelintegrally interconnected to said countersink and extending upwardlytherefrom to an elevation at least about the elevation of said crown;and an opening means positioned on said central panel which ispositioned at an elevation no greater than said uppermost edge of saidcentral panel, wherein the beverage can may be selectively opened. 21.The beverage can end of claim 20, wherein said opening means comprises apull tab.
 22. The beverage can end of claim 20, wherein a lowermostportion of said countersink is no greater than about 0.270 inches fromsaid crown.
 23. The beverage can end of claim 20, wherein at least aportion of said central panel has a non-linear, arcuate shape.